Snubber for dipper door on power shovels



L. W. EDWARDS ET AL SNUBBER FOR DIPPER DOOR ON POWER SHOVELS July 22, 1952 2 SHEETS-SHEET 1 Filed June 10, 1949 liwe'nfrs Lewis Wikfivardsia By I Ciefala? fimsi fofi Awv y 22, 1952 w. EDWARDS ETAL 2,504,221

SNUBBER FOR DIPPER DOOR ON POWER SHOVELS 2 SHEETSSHEET 2 Filed June 10, 1949 .LICIZG.

Lewis Wfi'dwards'fi; Gerald VomSiroh i p y//%% Patented July 22, 1952 SNUBBER FOR, DIPPEB nooRoN rowan snovELs Lewis W. Edwards. Lancaster, Pa 'and Gerald Von Stroh, Huntington, W. Va., assignors to Lukens Steel Company, Coatesville, Pa., a core poration of Pennsylvania Application June 10, 1949. Serial No. 98,376

This invention relates new and useful irnprovements in snubbing or damping devices, and relates more particularly to devices for 'snubbing or damping free swinging movement of hi ged members such as, for example, the doors of excavating shovels or scoops.

In the case of free swingingmembers suchas the doors of excavating shovels and the like, it isfrequently desirable to restrain free swinging movement of such members in order to prevent possible damage to the equipment and to personnel, and the principal object ofthe present invention is to provide a novel means for snubbing' ordamping free swinging'movement of the hinged members which is highly efficient and effective in operation and use. Another object of the invention is to provide snubbing or damping means as set forth which is of relatively simplified construction and comparatively inexpensive to manufacture.

A further object of the invention is to provide set forth and described with reference t the accompanying drawings, in which:

Fig. 1 is a side elevational view of a conventional type scoop or shovel customarily employed for excavating work;

Fig. 2 is a rear elevational view thereof; I

Fig. 3 is an enlarged fragmentary view in side elevation of the snubber mechanism;

Fig. 4 is a rear elevational view of the disclosure in Fig. 3;

Fig. 5 is an enlarged sectional view on line 55, Fig. 4; 1

Fig. 6 is an enlarged sectional view on line 6 6, Fig. 4.

Referring now more particularly to the draw- -in'gs, reference numeral designatesg'enerally a scoop or shovel of the type usually employed on power shovels and like excavating equipment. The scoop or shovel I is supported bya. bale 2 pivoted to the top thereof as indicated at 3,

and a suitable door 4 is. provided at the bottom 9 Claims. (01. 21 E146) :tio'nto free swinging movement of the" door 4 shovel.

vertically extending rib ll,

According to the present invention the arm portions 5 of the door 4 are each pivotally connected to suitable devices for snubbing or damping free swinging movement of the doorlwhen it is unlatched to discharge the contents of the In the illustrated embodiment of the invention two snubbing devices are utilized but since they are identical only one of them need be. described in detail. Thus, each door arm 5 is pivotally connected by a link 1 to the depending ear portions 8 of a bracket 9. The bracket 9 carries a pair of pins ID arranged in spaced relation respectively adjacent the opposite ends of the bracket 9. As shown, these pins l0 project inwardly from the bracket 9 and have their projecting portions equally spaced at opposite sides of a vertically extending rib H secured to -or forming a part of the rearward or back wall spaced ear portions I (5 which are provided at the outer sidesof brake shoes l6. These brake shoes 16 are faced with suitable friction material I! and are disposed slidably within generally channel-shaped guides H! which providesuitable brake surfaces IQ for engagement by the friction material IT. The guides are secured in back-toback relation at opposite sides of the aforesaid for example, as shown in Figs. 5 and 6. Referring to Fig. 3 of the drawing, in order to insure against the brake shoes i6 looking or galling in their guides 18, it is desirable that the force imparted to the snubber by the links 1 upon initial opening of the door (represented by broken line F) pass a short distance below the center of the pins [4 v on which the levers are pivoted.

The upper end portions 29 of the levers l3 curve upwardly and outwardly from their mounting pins l4, and their upper extremities are connected together by means of -a rod 2| which has its opposite end portions threaded to receive nuts or other securing means 22. By this construction it will be observed that by adjusting the nuts .22 on the rod 2| the pressure of thebrake shoes It. and their frictional material I! upon the brake surfaces of the guide members It may be increased or decreased as described thus increasing or decreasing the frictional resistance to sliding. of the brake shoes 16 in the, guide channels [8 consequently the snubbing or restrainingacserved that the present invention provides :novelmeans for snubbing r damping the free swinging movement of the hinged members which-is highly efficient and effective in operation. The

invention also provides novel snubbing or-damp-: ing means which is positive in its action, is fool' proof and requires substantially no maintenance or up-keep. In addition, the device of the pres-.

ent invention is of relatively simplified construc tion and is comparatively inexpensive to manufacture.

While a-particular embodiment of the present invention has been illustrated and described herein, it'is not intended to limit the invention with said brake surfaces, levers pivotally mounted intermediate their ends on said brake shoes and having one end pivotally mounted on said pin, and means acting on other ends of the levers operable to maintain the brake shoes in predetermined constant pressure engagement with said brake surfaces.

4. A snubber device for retarding free swinging movement of a hinged member, compr'ming ,fixedly mounted means providing a plurality of parallel plane brake surfaces, a bracket adjacent said brake surfaces, means carried by the hinged member for actuating said bracket lengthwise of thebrak'e surfaces, a brake shoe disposed in sliding engagement with each brake surface,

. levers carried by said bracket connected respecto such disclosure and changes and modifications maybe made therein and thereto within the scope of the following claims. I

We claim:

1. Asnubber device for retarding free'swinging movement of a hinged member, comprising fixedly mounted means having oppositely facing parallel brake surfaces extending normal to the hinge axis of the member, 'a bracket adjacent said brake surfaces and pivotally connected'to the hinged member for actuation thereby in a direction longitudinally -'of said fixedly mounted means, brake shoes disposed in sliding engagement with said brake surfaces, levers pivotally mounted intermediate their ends on said brake shoes and having one end pivotally connected to said-bracket, and means acting continuously-on the other ends of the levers operable to maintain said brake shoes in predetermined constant presmounted intermediate their ends on said brake shoes and having "one end pivotally connected to said bracket, an adjustable connection between the other ends of the levers, and means continuously acting on said other ends of the levers operable to maintain the brake shoesin predetermined constant pressure engagement with said brake surfaces, said means being adjustable to vary the contact pressure of the shoeson said surfaces to thereby regulate the snubbing action upon the hinged member.

3. A snubber device forretarding free swinging movement of a hinged member, comprising fixedly mounted means having'oppositely facing parallel brake surfaces extending normal to the hinge axis of the member, a bracket adjacent said brake surfaces and pivotally connected to the hingedmember for actuation thereby in a direction longitudinally of said fixedly mounted means, pins carried by said bracket and arranged respectively outwardly adjacent said brake surfaces, brake shoes disposed in sliding engagement tivelyto one of said brake shoes, and means acting continuously on said levers operable to maintain the brake shoes in predetermined constant pressure engagement with said brake surfaces.

' 5. Asnubber device for retarding free swinging movement of a hinged member, comprising fixedly mounted means providing a plurality of parallel plane brake surfaces, a-bracket adjacent said brake surfaces, means carried by the hinged member for actuating said bracket lengthwise of the brake surfaces, pins carried by said bracket, a brake. shoe disposed in sliding engagement with each brake surface, levers carried by each pin and connected to one of said brake shoes, and means :acting continuously on said levers operable to maintain the brake .shoes in predetermined constant pressure contact with saidbrake surfaces.

6. Inna :snubber device for .the hinged doors of "excavating shovels, guide members secured upon the shovel and providing parallel brake surfaces extending normal tothe hinge axis of the door, a bracket positioned crosswise of said the position of the bracket upon initial opening of the hinged door is angularly related to the pivotal mountingof each lever so that the line of force imparted by the bracket passes below the center of the pivotal mounting of the lever.

8. In a snubber device for hinged doors of excavating shovels, guide members secured upon the shovel and providing parallel brake surfaces extending normal to the hinge axis of the door,

abracket positioned crosswise of said brake surfaces and pivotally connected to the door "for actuation thereby in a direction longitudinally of the brake surfaces, brake shoes having friction material thereon disposed in sliding engagement with said said brake surfaces, levers pivotally mounted intermediate their ends on said brake shoes and having their lower ends pivotally carried .bygsaid bracket and their upper ends projected outwardly from the shovel, and adjustable connection between the upper ends of-the levers operable to vary the contact pressure of the shoes on said surfaces to thereby regulate LEWIS W. EDWARDS. GERALD VON STROH.

6 REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date Dick Aug. 13, 1878 Nelson Jan. 5, 1915 Borgmann Oct. 9, 1917 Kimball June 24, 1930 Davidson May 30, 1939 Burdick Jan. 27, 1948 

